#define PETSCMAT_DLL

/* 
        Provides an interface for the Matlab engine sparse solver

*/
#include "../src/mat/impls/aij/seq/aij.h"

#include "engine.h"   /* Matlab include file */
#include "mex.h"      /* Matlab include file */


EXTERN_C_BEGIN
#undef __FUNCT__  
#define __FUNCT__ "MatMatlabEnginePut_Matlab"
PetscErrorCode PETSCMAT_DLLEXPORT MatMatlabEnginePut_Matlab(PetscObject obj,void *mengine)
{
  PetscErrorCode ierr;
  Mat            B = (Mat)obj;
  mxArray        *mat; 
  Mat_SeqAIJ     *aij = (Mat_SeqAIJ*)B->data;

  PetscFunctionBegin;
  mat  = mxCreateSparse(B->cmap->n,B->rmap->n,aij->nz,mxREAL);
  //mat  = mxCreateSparse(((PetscObject)B)->cmap.n,((PetscObject)B)->rmap.n,((Mat_SeqAIJ*)aij)->nz,mxREAL); 
  ierr = PetscMemcpy(mxGetPr(mat),aij->a,aij->nz*sizeof(PetscScalar));CHKERRQ(ierr);
  /* Matlab stores by column, not row so we pass in the transpose of the matrix */
  ierr = PetscMemcpy(mxGetIr(mat),aij->j,aij->nz*sizeof(int));CHKERRQ(ierr);
  ierr = PetscMemcpy(mxGetJc(mat),aij->i,(B->rmap->n+1)*sizeof(int));CHKERRQ(ierr);

  /* Matlab indices start at 0 for sparse (what a surprise) */
  
  ierr = PetscObjectName(obj);CHKERRQ(ierr);
  engPutVariable((Engine *)mengine,obj->name,mat);
  PetscFunctionReturn(0);
}
EXTERN_C_END

EXTERN_C_BEGIN
#undef __FUNCT__  
#define __FUNCT__ "MatMatlabEngineGet_Matlab"
PetscErrorCode PETSCMAT_DLLEXPORT MatMatlabEngineGet_Matlab(PetscObject obj,void *mengine)
{
  PetscErrorCode ierr;
  int            ii;
  Mat            mat = (Mat)obj;
  Mat_SeqAIJ     *aij = (Mat_SeqAIJ*)mat->data;
  mxArray        *mmat; 

  PetscFunctionBegin;
  ierr = MatSeqXAIJFreeAIJ(mat,&aij->a,&aij->j,&aij->i);CHKERRQ(ierr);

  mmat = engGetVariable((Engine *)mengine,obj->name);

  aij->nz           = (mxGetJc(mmat))[mat->rmap->n];
  ierr  = PetscMalloc3(aij->nz,PetscScalar,&aij->a,aij->nz,PetscInt,&aij->j,mat->rmap->n+1,PetscInt,&aij->i);CHKERRQ(ierr);
  aij->singlemalloc = PETSC_TRUE;

  ierr = PetscMemcpy(aij->a,mxGetPr(mmat),aij->nz*sizeof(PetscScalar));CHKERRQ(ierr);
  /* Matlab stores by column, not row so we pass in the transpose of the matrix */
  ierr = PetscMemcpy(aij->j,mxGetIr(mmat),aij->nz*sizeof(int));CHKERRQ(ierr);
  ierr = PetscMemcpy(aij->i,mxGetJc(mmat),(mat->rmap->n+1)*sizeof(int));CHKERRQ(ierr);

  for (ii=0; ii<mat->rmap->n; ii++) {
    aij->ilen[ii] = aij->imax[ii] = aij->i[ii+1] - aij->i[ii];
  }

  ierr = MatAssemblyBegin(mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
  ierr = MatAssemblyEnd(mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);

  PetscFunctionReturn(0);
}
EXTERN_C_END

#undef __FUNCT__  
#define __FUNCT__ "MatSolve_Matlab"
PetscErrorCode MatSolve_Matlab(Mat A,Vec b,Vec x)
{
  PetscErrorCode ierr;
  const char     *_A,*_b,*_x;

  PetscFunctionBegin;
  /* make sure objects have names; use default if not */
  ierr = PetscObjectName((PetscObject)b);CHKERRQ(ierr);
  ierr = PetscObjectName((PetscObject)x);CHKERRQ(ierr);

  ierr = PetscObjectGetName((PetscObject)A,&_A);CHKERRQ(ierr);
  ierr = PetscObjectGetName((PetscObject)b,&_b);CHKERRQ(ierr);
  ierr = PetscObjectGetName((PetscObject)x,&_x);CHKERRQ(ierr);
  ierr = PetscMatlabEnginePut(PETSC_MATLAB_ENGINE_(((PetscObject)A)->comm),(PetscObject)b);CHKERRQ(ierr);
  ierr = PetscMatlabEngineEvaluate(PETSC_MATLAB_ENGINE_(((PetscObject)A)->comm),"%s = u%s\\(l%s\\(p%s*%s));",_x,_A,_A,_A,_b);CHKERRQ(ierr);
  ierr = PetscMatlabEngineEvaluate(PETSC_MATLAB_ENGINE_(((PetscObject)A)->comm),"%s = 0;",_b);CHKERRQ(ierr);
  /* ierr = PetscMatlabEnginePrintOutput(PETSC_MATLAB_ENGINE_(((PetscObject)A)->comm),stdout);CHKERRQ(ierr);  */
  ierr = PetscMatlabEngineGet(PETSC_MATLAB_ENGINE_(((PetscObject)A)->comm),(PetscObject)x);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

#undef __FUNCT__  
#define __FUNCT__ "MatLUFactorNumeric_Matlab"
PetscErrorCode MatLUFactorNumeric_Matlab(Mat F,Mat A,const MatFactorInfo *info)
{
  PetscErrorCode ierr;
  size_t         len;
  char           *_A,*name;

  PetscFunctionBegin;
  ierr = PetscMatlabEnginePut(PETSC_MATLAB_ENGINE_(((PetscObject)A)->comm),(PetscObject)A);CHKERRQ(ierr);
  _A   = ((PetscObject)A)->name;
  ierr = PetscMatlabEngineEvaluate(PETSC_MATLAB_ENGINE_(((PetscObject)A)->comm),"[l_%s,u_%s,p_%s] = lu(%s',%g);",_A,_A,_A,_A,info->dtcol);CHKERRQ(ierr);
  ierr = PetscMatlabEngineEvaluate(PETSC_MATLAB_ENGINE_(((PetscObject)A)->comm),"%s = 0;",_A);CHKERRQ(ierr);
  ierr = PetscStrlen(_A,&len);CHKERRQ(ierr);
  ierr = PetscMalloc((len+2)*sizeof(char),&name);CHKERRQ(ierr);
  sprintf(name,"_%s",_A);
  ierr = PetscObjectSetName((PetscObject)F,name);CHKERRQ(ierr);
  ierr = PetscFree(name);CHKERRQ(ierr);
  F->ops->solve              = MatSolve_Matlab;
  PetscFunctionReturn(0);
}

#undef __FUNCT__  
#define __FUNCT__ "MatLUFactorSymbolic_Matlab"
PetscErrorCode MatLUFactorSymbolic_Matlab(Mat F,Mat A,IS r,IS c,const MatFactorInfo *info)
{
  PetscFunctionBegin;
  if (A->cmap->N != A->rmap->N) SETERRQ(PETSC_ERR_ARG_SIZ,"matrix must be square"); 
  F->ops->lufactornumeric    = MatLUFactorNumeric_Matlab;
  PetscFunctionReturn(0);
}

EXTERN_C_BEGIN 
#undef __FUNCT__  
#define __FUNCT__ "MatFactorGetSolverPackage_seqaij_matlab"
PetscErrorCode MatFactorGetSolverPackage_seqaij_matlab(Mat A,const MatSolverPackage *type)
{
  PetscFunctionBegin;
  *type = MAT_SOLVER_MATLAB;
  PetscFunctionReturn(0);
}
EXTERN_C_END

#undef __FUNCT__  
#define __FUNCT__ "MatGetFactor_seqaij_matlab"
PetscErrorCode MatGetFactor_seqaij_matlab(Mat A,MatFactorType ftype,Mat *F)
{
  PetscErrorCode ierr;

  PetscFunctionBegin;
  if (A->cmap->N != A->rmap->N) SETERRQ(PETSC_ERR_ARG_SIZ,"matrix must be square"); 
  ierr                        = MatCreate(((PetscObject)A)->comm,F);CHKERRQ(ierr);
  ierr                        = MatSetSizes(*F,A->rmap->n,A->cmap->n,A->rmap->n,A->cmap->n);CHKERRQ(ierr);
  ierr                        = MatSetType(*F,((PetscObject)A)->type_name);CHKERRQ(ierr);
  ierr                        = MatSeqAIJSetPreallocation(*F,0,PETSC_NULL);CHKERRQ(ierr);
  (*F)->ops->lufactorsymbolic = MatLUFactorSymbolic_Matlab;
  ierr = PetscObjectComposeFunctionDynamic((PetscObject)(*F),"MatFactorGetSolverPackage_C","MatFactorGetSolverPackage_seqaij_matlab",MatFactorGetSolverPackage_seqaij_matlab);CHKERRQ(ierr);

  (*F)->factor                = MAT_FACTOR_LU;
  PetscFunctionReturn(0);
}


/* --------------------------------------------------------------------------------*/
#undef __FUNCT__  
#define __FUNCT__ "MatILUDTFactor_Matlab"
PetscErrorCode MatILUDTFactor_Matlab(Mat A,IS isrow,IS iscol,const MatFactorInfo *info)
{
  PetscErrorCode ierr;
  size_t         len;
  char           *_A,*name;
  PetscReal      dt,dtcol;
  Mat            F;

  PetscFunctionBegin;
  if (info->dt == PETSC_DEFAULT)      dt    = .005;
  if (info->dtcol == PETSC_DEFAULT)   dtcol = .01;
  ierr = MatGetFactor(A,MAT_SOLVER_MATLAB,MAT_FACTOR_ILU,&F);CHKERRQ(ierr);
  F->ops->solve           = MatSolve_Matlab;
  F->factor               = MAT_FACTOR_LU;
  ierr = PetscMatlabEnginePut(PETSC_MATLAB_ENGINE_(((PetscObject)A)->comm),(PetscObject)A);CHKERRQ(ierr);
  _A   = ((PetscObject)A)->name;
  ierr = PetscMatlabEngineEvaluate(PETSC_MATLAB_ENGINE_(((PetscObject)A)->comm),"info_%s = struct('droptol',%g,'thresh',%g);",_A,dt,dtcol);CHKERRQ(ierr);
  ierr = PetscMatlabEngineEvaluate(PETSC_MATLAB_ENGINE_(((PetscObject)A)->comm),"[l_%s,u_%s,p_%s] = luinc(%s',info_%s);",_A,_A,_A,_A,_A);CHKERRQ(ierr);
  ierr = PetscMatlabEngineEvaluate(PETSC_MATLAB_ENGINE_(((PetscObject)A)->comm),"%s = 0;",_A);CHKERRQ(ierr);

  ierr = PetscStrlen(_A,&len);CHKERRQ(ierr);
  ierr = PetscMalloc((len+2)*sizeof(char),&name);CHKERRQ(ierr);
  sprintf(name,"_%s",_A);
  ierr = PetscObjectSetName((PetscObject)F,name);CHKERRQ(ierr);
  ierr = PetscFree(name);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

#undef __FUNCT__  
#define __FUNCT__ "MatFactorInfo_Matlab"
PetscErrorCode MatFactorInfo_Matlab(Mat A,PetscViewer viewer)
{
  PetscErrorCode ierr;
  
  PetscFunctionBegin; 
  ierr = PetscViewerASCIIPrintf(viewer,"Matlab run parameters:  -- not written yet!\n");CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

#undef __FUNCT__  
#define __FUNCT__ "MatView_Matlab"
PetscErrorCode MatView_Matlab(Mat A,PetscViewer viewer) 
{
  PetscErrorCode    ierr;
  PetscTruth        iascii;
  PetscViewerFormat format;

  PetscFunctionBegin;
  ierr = MatView_SeqAIJ(A,viewer);CHKERRQ(ierr);
  ierr = PetscTypeCompare((PetscObject)viewer,PETSC_VIEWER_ASCII,&iascii);CHKERRQ(ierr);
  if (iascii) {
    ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
    if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
      ierr = MatFactorInfo_Matlab(A,viewer);
    }
  }
  PetscFunctionReturn(0);
}


/*MC
  MAT_SOLVER_MATLAB - "matlab" - Providing direct solvers (LU and QR) and drop tolerance
  based ILU factorization (ILUDT) for sequential matrices via the external package Matlab.


  Works with MATSEQAIJ matrices.

  Options Database Keys:
. -pc_factor_mat_solver_type matlab - selects Matlab to do the sparse factorization


  Level: beginner

.seealso: PCLU

.seealso: PCFactorSetMatSolverPackage(), MatSolverPackage
M*/